The present invention relates to seal systems for use with industrial process pressure transmitters. More specifically, the present invention relates to such seal systems that include a seal that couples a pressure to a coplanar inlet plate of a differential pressure transmitter.
Industrial process control systems are used to monitor and control industrial processes use to produce or transfer liquids or the like. In such systems, it is typically important to measure “process variables” such as temperatures, pressures, flow rates, and others. Process control transmitters are used to measure such process variables and transmit information related to the measured process variable back to a central location such as a central control room.
One type of process variable transmitter is a differential pressure transmitter which measures two pressures of process fluids and provides an output related to a pressure difference between the two measured pressures. This pressure difference may, in turn, represent a differential pressure, a flow rate, a level of process fluid in a vessel, or other process variable. The transmitter is configured to transmit information related to the differential pressure back to the central control room. The transmission is typically sent over a two wire process control loop, however, other communication techniques may be used, including wireless techniques.
The pressures must be coupled to the process variable transmitter through some type of process couplings. For example, the process fluid can comprise a component used in an industrial process such as natural gas, oil, etc. In certain process measurement applications, the pressure transmitter is located remotely relative to the pressurized process fluid, and pressures are physically conveyed from the process fluid to the pressure transmitter through a fluid link called a remote seal.
In some applications, an assembly of two seals couples two pressures (high side and low side pressures) to a coplanar inlet plate of a differential pressure transmitter. When one of the seals requires replacement, the assembly of two seals is disconnected from the coplanar inlet plate. Disconnection from the coplanar inlet plate results in breaking open both high and low side seal systems, and the entire assembly must be replaced at great expense. There is a need to improve seal systems that attach to coplanar inlet plates so that the cost of replacing a single damaged seal is reduced.